A typical alternating-current surface discharge panel used as a plasma display panel (hereinafter simply referred to as “panel”) has a large number of discharge cells that are formed between a front plate and a rear plate facing each other. The front plate has the following elements:                a plurality of display electrode pairs, each formed of a scan electrode and a sustain electrode, disposed on a front glass substrate parallel to each other; and        a dielectric layer and a protective layer formed so as to cover the display electrode pairs. The rear plate has the following elements:        a plurality of parallel data electrodes formed on a rear glass substrate;        a dielectric layer formed so as to cover the data electrodes;        a plurality of barrier ribs formed on the dielectric layer parallel to the data electrodes; and        phosphor layers formed on the surface of the dielectric layer and on the side faces of the barrier ribs.The front plate and the rear plate face each other so that the display electrode pairs and the data electrodes three-dimensionally intersect, and are sealed together. A discharge gas containing xenon in a partial pressure ratio of 5%, for example, is charged into the sealed inside discharge space. Discharge cells are formed in portions where the display electrode pairs face the data electrodes. In a panel having such a structure, gas discharge generates ultraviolet light in each discharge cell. This ultraviolet light excites the red (R), green (G), and blue (B) phosphors so that the phosphors emit the corresponding colors for color display on the panel.        
A subfield method is typically used as a method for driving the panel. In the subfield method, one field is divided into a plurality of subfields, and gradations are displayed by causing light emission or no light emission in each discharge cell in each subfield.
Each subfield has an initializing period, an address period, and a sustain period.
In the initializing period, an initializing waveform is applied to the respective scan electrodes to cause an initializing discharge in the respective discharge cells. This initializing discharge forms wall charge necessary for the subsequent address operation on the electrodes in the respective discharge cells. This discharge also generates priming particles (excitation particles for causing an address discharge) for stably causing the address discharge in the respective discharge cells.
In the address period, a scan pulse is applied to the scan electrodes, and an address pulse is selectively applied to the data electrodes according to the signals of an image to be displayed. Thereby, an address discharge is selectively caused to form wall charge in the discharge cells to be lit (hereinafter, this operation being also referred to as “addressing”).
In the sustain period, sustain pulses corresponding in number to the luminance to be displayed are applied to display electrode pairs, each formed of a scan electrode and a sustain electrode. Thereby, a sustain discharge is caused in the discharge cells having undergone the address discharge, and thus the phosphor layers in the discharge cells are caused to emit light. In this manner, an image is displayed.
As one of the subfield methods, the following driving method is disclosed. In this driving method, an initializing discharge is caused with a gently-changing voltage waveform. Further, the initializing discharge is selectively caused in the discharge cells having undergone a sustain discharge. This operation minimizes the light emission unrelated to gradation display and improves the contrast ratio.
Specifically, in the initializing period of one subfield among a plurality of subfields, an all-cell initializing operation for causing an initializing discharge in all the discharge cells is performed. In the initializing periods of the other subfields, a selective initializing operation for causing an initializing discharge only in the discharge cells having undergone a sustain discharge in the immediately preceding sustain period is performed. With such driving, the luminance in an area displaying a black picture (hereinafter, simply referred to as “luminance of a black level”) that is changed by light emission unrelated to image display is determined by a weak light emission in the all-cell initializing operation, and an image having a high contrast can be displayed (see Patent Literature 1, for example).
The following driving method is also disclosed. In this driving method, an initializing waveform that has the following two portions is applied in the initializing periods: a portion where the voltage rises with a gentle gradient; and a portion where the voltage falls with a gentle gradient. Immediately before this application, a weak discharge is caused between the sustain electrodes and scan electrodes in all the discharge cells. This operation can improve the visibility of black in the panel (see Patent Literature 2, for example).
With the recent increases in the definition of a panel, the discharge cells have been further miniaturized. The following phenomena are confirmed in such miniaturized discharge cells. The wall charge formed in such discharge cells by the initializing discharge is likely to be changed by the influence of the address discharge or sustain discharge caused in the adjacent discharge cells. The wall charge in the discharge cells undergoing no sustain discharge is likely to be changed by the influence of the adjacent discharge cells undergoing a sustain discharge, in the subfield where a large number of sustain pulses are generated in the sustain period. When unnecessary wall charge excessively accumulates in discharge cells, an erroneous address discharge (hereinafter, also referred to as “false discharge”) can occur in the discharge cells where the address discharge is not to be caused. Such a false discharge deteriorates the image display quality.